Many types of fasteners are known in the art for firmly holding a variety of components together. For example, railroad drive spikes are used to hold tie plates to wooden ties. Drive spikes may also be used to hold together bridges, trestles, wooden piers, and docks.
Typically, for railways, the steel rails have mounting flanges adapted to mate with metallic plates. The metallic plates also contact the wooden ties and are adapted to receive drive spikes to secure the rails to the ties. The spikes are inserted through openings or recesses in the metal plate and driven into the wooden ties. Thus, the steel rails are secured to the wooden ties via the metal plates and the drive spikes.
In use, the drive spikes eventually loosen from the wooden ties as a result of events such as repeated train crossings and environmental conditions. The weight and vibrations from the passing trains cause the spikes to loosen and enlarge the entry holes within the wooden ties. Environmental conditions such as humidity, temperature changes, rain, snow, etc. may also cause the drive spikes to become loosed within the wooden ties. Additionally, vandals may purposely loosen or remove the drive spikes. As the drive spikes become loose, the holes into which the drive spikes are inserted in the wooden ties enlarge. The enlarged holes then become further exposed to environmental conditions, causing the wood to decay more quickly.
Tightening or replacement of the drive spikes is often difficult and costly. Removal of a drive spike may cause further destruction to the wooden tie, making the replacement of the drive spike nearly impossible. Once the drive spike is loosened and/or the wood becomes damaged, the entire wooden tie often requires replacement in order to provide a steel rail that is securely fastened to the wooden tie.
Similar to the railway example, the bridge, trestle, pier and dock drive spike connections are also subject to vibrational and environmental stresses, as well as vandalism, that cause unwanted loosening of the drive spikes within the substrate. Once the drive spike loosens, the substrate into which the spike is driven usually must be replaced in order to securely fasten the bridge, trestle, etc. to the substrate. Replacement of the drive spike itself is generally insufficient to securely fasten objects to the substrate. The enlarged hole in the substrate causes the substrate to become more quickly degraded and thus prevents the drive spike from securely gripping the substrate.
Therefore, it is an object of the present invention to provide a drive spike that securely fastens an object to a substrate, such as wood, and prevents inadvertent loosening or removal of the drive spike from the substrate, thus further reducing the requirement for replacement of the substrate due to damage caused by the insecure fastening of an object to a substrate.